Anyone Towing 2021 T@B400 with Lexus RX350

Sydmargo

Thinking of changing tow vehicle.

Horigan

It would be similar to a Highlander.  Plenty of discussions on Highlanders here.  I'm happy with mine.

annbythebay

We're just getting started with our 2024 Tab 400 and 2022 Lexus 350 RX with factory tow package. We've taken one fairly level 105 mile trip and had no problems. We love the trailer and the car, but I am nervous because the tow rating on the Lexus is 3500 pounds, which is very close to our trailer weight. We drive slowly never exceeding 55 mph and hope for the best. 

Does anyone have any tips on whether to use the manual shifting options vs the automatic transmission while towing? 

rfuss928

Your towing capacity is reduced pound for pound by everything you carry in the TV including driver and passenger.  With a 3500 pound maximum it is very likely you are over capacity when towing a T@B 400 loaded and ready to travel.  Please be very careful as road condition and/or emergency maneuvers can easily push loads well beyond the TV capabilities.

AnOldUR

rfuss928 said:

Your towing capacity is reduced pound for pound by everything you carry in the TV including driver and passenger.  

Towing capacity is reduced by everything you carry, but it's a non-specific term for all of the various tow ratings. Most vehicle manufactures list the gross trailer weight (GTW) as the tow rating in their literature. That is the rating for the weight of only the loaded trailer and doesn't consider what's in the tow vehicle. It's sometimes a confusing balancing act between all the various ratings. They all have to be considered, but I think that the combined rating (GCWR) is not stressed enough. That's the one that includes everything; driver, passengers, tow vehicle, trailer and all the gear and supplies loaded in both.  

Grumpy_G

rfuss928 said:

Your towing capacity is reduced pound for pound by everything you carry in the TV including driver and passenger.  With a 3500 pound maximum it is very likely you are over capacity when towing a T@B 400 loaded and ready to travel.  Please be very careful as road condition and/or emergency maneuvers can easily push loads well beyond the TV capabilities.

Basically yes however IIRC the tow rating is calculated with driver and some fuel. The tow rating is calculated from the gross combined weight rating (GCWR) determined using SAE J2807 (https://en.wikipedia.org/wiki/SAE_J2807) Often people refer to this number as "legal limit" but (disclaimer: IANAL) that is not strictly true. Pretty much any hot shot trucker (pickup and gooseneck trailer) registers their commercial vehicle for up to 38k or 40k combined which exceeds the factory GCWR for most trucks except the very latest generations. 
As long you are safe and prudent a couple of hundred pounds over GCWR will not get you in trouble as long as both the tow vehicle and the trailer are under their respective GVWR. Keep in mind that the tongue weight counts towards the weight of the tow vehicle although it is not actual mass in the vehicle. That can be a limiting factor for many smaller SUVs. 
Now a heavily overloaded combination, bad load distribution on the trailer, a trailer much longer/taller than the tow vehicle make it "unsafe and negligent" which does have legal ramifications.  

rfuss928

Unfortunately GCWR rating is rarely available for the light duty passenger vehicles many of us use for TVs. Given that and the common safety recommendation not to exceed 80% of rated towing capacity, subtracting TV payload from rated towing capacity is the prudent choice.  Using wishful rationalization to justify carrying excessive loads is unsafe and a risk to you and those traveling near you.

edit: corrected to GCWR  - thank you Grumpy_G

Horigan

@annbythebay, I think your main limiting factor will be the tongue load limit, which I believe is 350 lbs when the tow limit is 3500 lbs.  Toyota/Lexus manuals also require sway control of some sort for trailers over 2000 lbs.

In general, I find that once you confirm the trailer is under the capacity (GTW< 3500 lbs), the next limiting factor is the gross vehicle weight, GVWR, which needs to include all vehicle cargo, occupants, AND tongue load.

Grumpy_G

rfuss928 said:

Unfortunately GVWR rating is rarely available for the light duty passenger vehicles many of us use for TVs. 

Actually the GVWR is on the sticker in the door jamb, it's the GCWR that is not shown on the vehicle. Add to that that at least in the pickup truck world the GCWR and with that the tow rating can vary widely based on engine and axle ratios and it becomes very murky. 

phillm47

This may be helpful

https://www.curtmfg.com/towing-capacity